1. Field of the Invention
This invention relates to liquid-level float switches used for in-line and auxiliary applications, specifically to a float switch of sturdy construction that is primarily contemplated for use in condensate collection applications, but which is also useful in other fluid transport applications. The most preferred embodiment of the present invention is small and comprises a housing with a maximum height dimension of approximately two inches and a maximum width dimension of approximately three inches, including its connecting extension/arm that is used for fluid communication with a discharge line. Also in the present invention, an adjustable float switch body is positioned for vertical movement within the housing, guided by a concentrically positioned shaft that is secured to the enlarged upper portion of the housing with fastening means, such as but not limited to a lock-nut. The amount of float switch body displacement is preferably adjustable and defined by the positions of the lock-nut and a disk-shaped bottom stop when both are secured to the shaft. It is contemplated for both the lock-nut and stop to be removably connected to the shaft so that the float switch body can be removed when needed for maintenance, inspection, and replacement purposes. The float switch body has a large surface area for enhanced buoyancy and improved responsiveness during operation, with the housing closely positioned around the float switch body and having an open bottom end that is closed by a securely affixed cap or other closure that can be easily removed to check for debris in the main or auxiliary fluid line to which it is connected. Preferably, but not limited thereto, the bottom closure is threaded and attached with an o-ring to provide a leak-resistant connection. As the upper portion of the housing is enlarged, no air vent openings are required to prevent an airlock malfunction. Alignment guides are also preferably incorporated as a part of the extension/arm to assist in obtaining a level positioning of the housing during installation for unimpeded and proper float switch body operation, and maintaining the optimal orientation during long term operation. The alignment guides can have many configurations, such as but not limited to one or more of the following, ridges, notches, pointed teeth, square teeth, a scalloped pattern in combination with complementary pointed teeth, and/or any other configuration that incrementally provides a ratcheting type of engagement for alignment and level-preserving purposes. Electrical wires extending through the top of the housing provide the electrical connection needed between the rising float switch body and a fluid producing source, so that collection of a very small amount of water in the housing as a result of hindered or clogged fluid flow in the fluid discharge line to which the housing is connected, such as but not limited to 7.5 ml or 1.5 teaspoons, is able to activate the float switch body and promptly interrupt operation of the fluid producing source. The configuration of the present invention housing that allows positioning of the bottom of the float switch body lower than the discharge line of a fluid producing system, ensures that a very small amount of collected fluid will cause the termination of fluid production by the system. Since the float switch body does not remain in contact with condensate and added maintenance fluids, and only a small amount of collected condensate triggers the switch body, it remains responsive and functional, thereby causing the air conditioning coils to last longer for release of less ozone depleting chemicals annually into the environment. The responsiveness and reliable functionality of the present invention also promotes efficient operation of higher energy rated air conditioning systems that produce a significantly larger amount of condensate due to the present invention being able to terminate the production of condensate after only a very small amount of it is collected after a blockage occurs in the discharge line. In its basic configuration the present invention float switch is ready for auxiliary use, and with the use of one or more connecting accessories, it can be readily adapted for in-line use.
2. Description of the Related Art
When air conditioning condensate and other fluids travel in discharge lines, there is often a risk of overflow or back-up into the system producing it. As a result, liquid-level float switches have been employed in-line with such discharge lines, and also in an auxiliary capacity, to shut-off the source of fluid flow into the line when the amount of fluid therein exceeds a predetermined depth. However, currently known float switches are deficient in many ways and thereby subject to malfunction, less responsive operation, more costly installation, and/or unstable installation. Overflow and condensate back-up, particularly in older systems where back-up is repeatedly encountered, can lead to corrosion of air conditioning coils, causing freon and/or other ozone damaging chemicals to be lost to the atmosphere. Many prior art float switches tend to be at risk for malfunction since they are in constant contact with the fluid in the discharge line, and subject to impaired operation as a result of such things as rust, algae, mold, and/or other debris that grows or accumulates in the discharge line over time. Also, some prior art liquid-level float switches tend to have float switch bodies that wobble relative to the shaft with which they are associated, a condition that can lead to less responsive operation or malfunction that may worsen over time. In addition, some prior art float switches are at risk for premature malfunction as a result of being made from materials that are not completely corrosion-resistant. In contrast, the present invention is made from plastic that is impervious to corrosion. Also, its float switch body is wider than those of known prior art float switches for greater water displacement, however, its housing has a small width dimension for easy installation in the tight spaces in residential construction often permitted for air handler location and the connection of condensate discharge lines. In addition, the present invention uses less water to activate electrical shut-off for a faster response time than prior art devices as the bottom portion of its float switch body sits below the discharge line, the extension/arm of the present invention housing has a ratcheting-type leveling-assist feature for the float switch body to facilitate level installation and maintenance of the established optimum orientation during its operation, no holes are needed in the housing to prevent air-lock malfunction as its housing is configured with an enlarged upper surface or bubble that provides a continuous approximately three-fourths inch water passage throughout, the float switch body does not constantly sit in water where it could malfunction due to an accumulation of algae/rust/mold/debris over time, to provide a more secure installation than prior art devices its threaded connections comprise the standard fittings used in threaded pipe connections and not the coarse hose bib threads typically used in the majority of prior art devices, and its bottom cap or other bottom closure permits easy access to the float switch body and cleanout of algae/mold/rust/debris from the housing that could otherwise cause malfunction of the float switch body. In combination with connecting accessories, the housing can be used in a variety of auxiliary applications or be installed for in-line use. Since the present invention is small and has a simple design, it uses less materials for its construction and thereby is also cost effective to make and use. Within the next few years, higher rated air conditioning units will be required by law for fuel efficiency. The large coils used therein will create more condensate. Since condensate continues to drip for ten to fifteen minutes after the air conditioning unit has been shut off, it is very important for in-line and auxiliary switches to be responsive to very small amounts of water and be subject to minimal risk of malfunction, thus having a significant positive impact on the environment. The present invention is configured to be responsive to and meet the needs of the higher rated systems, as well as those of current systems. Without a responsive condensate/fluid flow shut-off switch, air conditioning systems with a higher energy rating would more quickly encounter overflow and back-up problems and their overall efficiency would be diminished. Therefore, in addition to having a significant positive impact on the environment, by promoting efficient use of the higher energy rated air conditioning systems, widespread use of the present invention will also have a significant impact on energy savings in the United States. No condensate/fluid flow shut-off switch is known with all of the features and advantages of the present invention.